data/glr.cc

   1 # C++ GLR skeleton for Bison
   2 # Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
   3 # Free Software Foundation, Inc.
   4
   5 # This program is free software: you can redistribute it and/or modify
   6 # it under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation, either version 3 of the License, or
   8 # (at your option) any later version.
   9 #
  10 # This program is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 # GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License
  16 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17
  18
  19 # This skeleton produces a C++ class that encapsulates a C glr parser.
  20 # This is in order to reduce the maintenance burden.  The glr.c
  21 # skeleton is clean and pure enough so that there are no real
  22 # problems.  The C++ interface is the same as that of lalr1.cc.  In
  23 # fact, glr.c can replace yacc.c without the user noticing any
  24 # difference, and similarly for glr.cc replacing lalr1.cc.
  25 #
  26 # The passing of parse-params
  27 #
  28 #   The additional arguments are stored as members of the parser
  29 #   object, yyparser.  The C routines need to carry yyparser
  30 #   throughout the C parser; that's easy: make yyparser an
  31 #   additional parse-param.  But because the C++ skeleton needs to
  32 #   know the "real" original parse-param, we save them
  33 #   (b4_parse_param_orig).  Note that b4_parse_param is overquoted
  34 #   (and c.m4 strips one level of quotes).  This is a PITA, and
  35 #   explains why there are so many levels of quotes.
  36 #
  37 # The locations
  38 #
  39 #   We use location.cc just like lalr1.cc, but because glr.c stores
  40 #   the locations in a union, the position and location classes
  41 #   must not have a constructor.  Therefore, contrary to lalr1.cc, we
  42 #   must not define "b4_location_constructors".  As a consequence the
  43 #   user must initialize the first positions (in particular the
  44 #   filename member).
  45
  46 # We require a pure interface using locations.
  47 m4_define([b4_percent_define(locations)], [])
  48 m4_define([b4_pure_flag],      [1])
  49
  50 # The header is mandatory.
  51 b4_defines_if([],
  52               [b4_fatal([b4_skeleton[: using %%defines is mandatory]])])
  53
  54 m4_include(b4_pkgdatadir/[c++.m4])
  55 m4_include(b4_pkgdatadir/[location.cc])
  56
  57 m4_define([b4_parser_class_name],
  58           [b4_percent_define_get([[parser_class_name]])])
  59
  60 # Save the parse parameters.
  61 m4_define([b4_parse_param_orig], m4_defn([b4_parse_param]))
  62
  63
  64 # b4_yy_symbol_print_generate
  65 # ---------------------------
  66 # Bypass the default implementation to generate the "yy_symbol_print"
  67 # and "yy_symbol_value_print" functions.
  68 m4_define([b4_yy_symbol_print_generate],
  69 [[
  70 /*--------------------.
  71 | Print this symbol.  |
  72 `--------------------*/
  73
  74 ]b4_c_ansi_function_def([yy_symbol_print],
  75     [static void],
  76     [[FILE *],               []],
  77     [[int yytype],           [yytype]],
  78     [[const b4_namespace_ref::b4_parser_class_name::semantic_type *yyvaluep],
  79                              [yyvaluep]],
  80     [[const b4_namespace_ref::b4_parser_class_name::location_type *yylocationp],
  81                              [yylocationp]],
  82     b4_parse_param)[
  83 {
  84 ]b4_parse_param_use[]dnl
  85 [  yyparser.yy_symbol_print_ (yytype, yyvaluep]b4_locations_if([, yylocationp])[);
  86 }
  87 ]])
  88
  89
  90 # Declare yyerror.
  91 m4_append([b4_post_prologue],
  92 [b4_syncline([@oline@], [@ofile@])
  93
  94 b4_c_ansi_function_decl([yyerror],
  95     [static void],
  96     [[b4_namespace_ref::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
  97     b4_parse_param,
  98     [[const char* msg], [msg]])])
  99
 100
 101 # Define yyerror.
 102 m4_append([b4_epilogue],
 103 [b4_syncline([@oline@], [@ofile@])[
 104 /*------------------.
 105 | Report an error.  |
 106 `------------------*/
 107
 108 ]b4_c_ansi_function_def([yyerror],
 109     [static void],
 110     [[b4_namespace_ref::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 111     b4_parse_param,
 112     [[const char* msg], [msg]])[
 113 {
 114 ]b4_parse_param_use[]dnl
 115 [  yyparser.error (*yylocationp, msg);
 116 }
 117
 118
 119 ]b4_namespace_open[
 120 ]dnl In this section, the parse param are the original parse_params.
 121 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
 122 [  /// Build a parser object.
 123   ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [
 124     :])[
 125 #if YYDEBUG
 126     ]m4_ifset([b4_parse_param], [  ], [ :])[yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
 127 #endif]b4_parse_param_cons[
 128   {
 129   }
 130
 131   ]b4_parser_class_name::~b4_parser_class_name[ ()
 132   {
 133   }
 134
 135   int
 136   ]b4_parser_class_name[::parse ()
 137   {
 138     return ::yyparse (*this]b4_user_args[);
 139   }
 140
 141 #if YYDEBUG
 142   /*--------------------.
 143   | Print this symbol.  |
 144   `--------------------*/
 145
 146   inline void
 147   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 148                            const semantic_type* yyvaluep, const location_type* yylocationp)
 149   {
 150     /* Pacify ``unused variable'' warnings.  */
 151     YYUSE (yyvaluep);
 152     YYUSE (yylocationp);
 153     switch (yytype)
 154       {
 155 ]b4_symbol_foreach([b4_symbol_printer])dnl
 156 [        default:
 157           break;
 158       }
 159   }
 160
 161
 162   void
 163   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 164                            const semantic_type* yyvaluep, const location_type* yylocationp)
 165   {
 166     *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm")
 167                << ' ' << yytname[yytype] << " ("
 168                << *yylocationp << ": ";
 169     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
 170     *yycdebug_ << ')';
 171   }
 172
 173   std::ostream&
 174   ]b4_parser_class_name[::debug_stream () const
 175   {
 176     return *yycdebug_;
 177   }
 178
 179   void
 180   ]b4_parser_class_name[::set_debug_stream (std::ostream& o)
 181   {
 182     yycdebug_ = &o;
 183   }
 184
 185
 186   ]b4_parser_class_name[::debug_level_type
 187   ]b4_parser_class_name[::debug_level () const
 188   {
 189     return yydebug;
 190   }
 191
 192   void
 193   ]b4_parser_class_name[::set_debug_level (debug_level_type l)
 194   {
 195     yydebug = l;
 196   }
 197
 198 #endif
 199 ]m4_popdef([b4_parse_param])dnl
 200 b4_namespace_close[
 201 ]])
 202
 203
 204 # Let glr.c believe that the user arguments include the parser itself.
 205 m4_ifset([b4_parse_param],
 206 [m4_pushdef([b4_parse_param],
 207             m4_dquote([[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]],]
 208 m4_defn([b4_parse_param])))],
 209 [m4_pushdef([b4_parse_param],
 210             [[[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]]]])
 211 ])
 212 m4_include(b4_pkgdatadir/[glr.c])
 213 m4_popdef([b4_parse_param])
 214
 215 m4_divert_push(0)
 216 @output(b4_spec_defines_file@)@
 217 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
 218              [2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009])[
 219
 220 /* C++ GLR parser skeleton written by Akim Demaille.  */
 221
 222 #ifndef PARSER_HEADER_H
 223 # define PARSER_HEADER_H
 224
 225 ]b4_percent_code_get([[requires]])[
 226
 227 #include <string>
 228 #include <iostream>
 229
 230 /* Using locations.  */
 231 #define YYLSP_NEEDED ]b4_locations_if([1], [0])[
 232
 233 ]b4_namespace_open[
 234   class position;
 235   class location;
 236 ]b4_namespace_close[
 237
 238 #include "location.hh"
 239
 240 /* Enabling traces.  */
 241 #ifndef YYDEBUG
 242 # define YYDEBUG ]b4_parse_trace_if([1], [0])[
 243 #endif
 244
 245 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 246    If N is 0, then set CURRENT to the empty location which ends
 247    the previous symbol: RHS[0] (always defined).  */
 248
 249 #ifndef YYLLOC_DEFAULT
 250 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
 251     do                                                                  \
 252       if (N)                                                            \
 253         {                                                               \
 254           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 255           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 256         }                                                               \
 257       else                                                              \
 258         {                                                               \
 259           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 260         }                                                               \
 261     while (/*CONSTCOND*/ 0)
 262 #endif
 263
 264 ]b4_namespace_open[
 265   /// A Bison parser.
 266   class ]b4_parser_class_name[
 267   {
 268   public:
 269 ]b4_public_types_declare[
 270
 271     /// Build a parser object.
 272     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 273     virtual ~]b4_parser_class_name[ ();
 274
 275     /// Parse.
 276     /// \returns  0 iff parsing succeeded.
 277     virtual int parse ();
 278
 279     /// The current debugging stream.
 280     std::ostream& debug_stream () const;
 281     /// Set the current debugging stream.
 282     void set_debug_stream (std::ostream &);
 283
 284     /// Type for debugging levels.
 285     typedef int debug_level_type;
 286     /// The current debugging level.
 287     debug_level_type debug_level () const;
 288     /// Set the current debugging level.
 289     void set_debug_level (debug_level_type l);
 290
 291   public:
 292     /// Report a syntax error.
 293     /// \param loc    where the syntax error is found.
 294     /// \param msg    a description of the syntax error.
 295     virtual void error (const location_type& loc, const std::string& msg);
 296
 297 #if YYDEBUG
 298   public:
 299     /// \brief Report a symbol value on the debug stream.
 300     /// \param yytype       The token type.
 301     /// \param yyvaluep     Its semantic value.
 302     /// \param yylocationp  Its location.
 303     virtual void yy_symbol_value_print_ (int yytype,
 304                                          const semantic_type* yyvaluep,
 305                                          const location_type* yylocationp);
 306     /// \brief Report a symbol on the debug stream.
 307     /// \param yytype       The token type.
 308     /// \param yyvaluep     Its semantic value.
 309     /// \param yylocationp  Its location.
 310     virtual void yy_symbol_print_ (int yytype,
 311                                    const semantic_type* yyvaluep,
 312                                    const location_type* yylocationp);
 313   private:
 314     /* Debugging.  */
 315     std::ostream* yycdebug_;
 316 #endif
 317
 318     /// \brief Reclaim the memory associated to a symbol.
 319     /// \param yymsg        Why this token is reclaimed.
 320     /// \param yytype       The symbol type.
 321     /// \param yyvaluep     Its semantic value.
 322     /// \param yylocationp  Its location.
 323     inline void yydestruct_ (const char* yymsg,
 324                              int yytype,
 325                              semantic_type* yyvaluep,
 326                              location_type* yylocationp);
 327
 328 ]b4_parse_param_vars[
 329   };
 330
 331 ]dnl Redirections for glr.c.
 332 b4_percent_define_flag_if([[global_tokens_and_yystype]],
 333 [b4_token_defines(b4_tokens)])
 334 [
 335 #ifndef YYSTYPE
 336 # define YYSTYPE ]b4_namespace_ref[::]b4_parser_class_name[::semantic_type
 337 #endif
 338 #ifndef YYLTYPE
 339 # define YYLTYPE ]b4_namespace_ref[::]b4_parser_class_name[::location_type
 340 #endif
 341
 342 ]b4_namespace_close[
 343
 344 ]b4_percent_code_get([[provides]])[]dnl
 345
 346 [#endif /* ! defined PARSER_HEADER_H */]
 347 m4_divert_pop(0)